A business transaction may comprise very complex processes. For example, business transactions like purchasing and procurement in a large company comprises many processes such as application, approval, keeping records for audits, and official classification, which results in a very complex workflow. To systematize such a complex workflow to construct (develop or integrate) a system (software), modeling schemes such as ITT (Information Through Timing) model, OSW (Office of Secretaries of War) model, SADT (Structured Analysis & Design Technique), and other common workflow diagrams or data flow diagrams (DFDs) are used. However, visualization with any of these schemes is difficult and cam be carried out inadequately.
On the other hand, the processes in a company may be frequently changed for improvement and enhancement. After constructing a system by systematizing these business processes, if improvements or changes are to be made to the system for business process reengineering, it is necessary to modify the system design and, sometimes, to review the earlier stages, such as requirements definition and external design. This involves significant effort, cost, and time. Further, in this situation, it is difficult for the system developer to respond to requests for the modification from the system users, flexibly and promptly.
Thus, when reengineering such systems, system developers must review the developed systems beginning with the initial stage of the development (requirements definition or external design) depending on the scale of the reengineering. In addition, verification for the reengineering may require time and cost equal to or greater than those in verification for new development. Moreover, even when only a part of the system is changed, all the associated parts have to be reviewed for any changes and influences on them. As a result, there are cases where a business transaction performed by system users is adapted to the system instead of the system adapted to the business transaction of the users. This has been a significant problem.